- Author: Kathy Keatley Garvey
So wrote two Casida lab alumni, UC Davis distinguished professor Bruce Hammock and Qing X. Li, a professor at the University of Hawaii, Manoa, in their recently published biographical memoir in the Royal Society of Chemistry journal.
Casida, a UC Berkeley professor of toxicology and nutritional science for 50 years, also taught environmental science, policy and management, before becoming an emeritus professor in 2014. However, he continued to do research and mentor students until his death at age 88. He was actively involved with the UC system and often served on exam committees at UC Davis.
Casida was elected a fellow of the National Academy of Sciences in 1991 and to the London- based Royal Society in 1998. He won the first International Award for Research in Pesticide Chemistry in 1971 and the 1978 Spencer Award for Research in Agricultural and Food Chemistry by the American Chemical Society. In 1993, he was awarded the Wolf Prize in Agriculture "for his pioneering studies on the mode of action of insecticides, design of safer pesticides and contributions to the understanding of nerve and muscle function in insects.”
“John's legacy is his science, and this knowledge fostered subsequent science,” wrote Hammock and Li, longtime collaborators and friends of Casida. “A second legacy is the scientists he mentored in his career and the next generation who grew up with tales of ‘when we were in John's laboratory'. At scientific meetings, there is always a period of informal ‘Casida tales' ranging from practical jokes that extend for decades to stories of John and the charming eccentrics in his laboratory.”
“There is also a uniform awe and respect among his alumni. John set a high standard of ethics as well as work ethic in the field…What drives any of us, and particularly John Casida? Clearly wealth and fame were not important drivers, but there was a competitive spirit. The success of his many alumni brought him pleasure. We are confident John appreciated the tremendous contribution his career made to pesticide toxicology, the environment, human health and agriculture.”
Casida alumnus Sarjeet Gill, now UC Riverside distinguished professor emeritus, described him “the preeminent toxicologist in the world.”
In their abstract, the authors pointed out that Casida's “research in pesticide toxicology led to more effective agricultural chemicals that are far safer for human and environmental health. He used pesticides as probes for his fundamental studies of metabolism and mode of action, resulting in great insight into biological chemistry and the underlying mechanisms of regulatory biology, ranging from voltage-gated sodium channels, through the ryanodine receptor and calcium regulation, the gamma-aminobutyric acid (GABA)-gated chloride channel, to the nicotinic acetylcholine receptors. These discoveries, among many others, have had a profound impact on pharmacology and toxicology.”
Casida's research career “started with the introduction of DDT into agricultural practice and continued to assist in the development of many pesticides that dominate the market today,” the authors wrote, that he “trained multiple generations of toxicologists who obtained leading positions in government, industry and academics.”
Casida, born Dec. 22, 1929, spent his formative years in Madison, Wis. He received three degrees at the University of Wisconsin: his bachelor's degree in entomology in 1951; his masters in biochemistry in 1952; and a doctorate in entomology and biochemistry in 1954. He joined the faculty at the University of Wisconsin for six years, advancing to full professor, and then accepted a faculty position at UC Berkeley, where he remained active in teaching and research until his death on June 30, 2018.
His wife, Katherine “Kati” Faustine Monson, a well-known artist, died in 2021. Survivors include two sons, Eric of BeRex Corp., Berkeley, and Mark, professor of theoretical chemistry, Grenoble-Alps University, Grenoble, France. Casida “loved laboratory science and this, coupled with insatiable curiosity and a gift for finding the unexpected, led to papers from his laboratory sparkling with creativity,” the authors shared. “He similarly loved teaching at all levels and had just finished grading the final examination in his toxicology class at the time of his passing.”
“The phrase ‘long and productive career' is often used in remembrances, but this phrase is seldom more appropriately applied than when it describes J. E. Casida,” Hammock and Li wrote. “His first lead author paper was published when he was an undergraduate in Science Magazine. John was productive until his last brief illness, and even during this period of hospitalization he was planning his next works.”
Professor Casida is sorely missed by his colleagues and the broad field of toxicology and pharmacology, they said.
- Author: Kathy Keatley Garvey
His seminar begins at 4:10 p.m. and also will be on Zoom:
https://ucdavis.zoom.us/j/95882849672.
Host is UC Davis distinguished professor James R. Carey, UC Davis Department of Entomology and Nematology.
"African Trypanosomiasis, also known as 'sleeping sickness,' is caused by microscopic parasites of the species Trypanosoma brucei," according to the Centers for Disease Control and Prevention. "It is transmitted by the tsetse fly (Glossina species), which is found only in sub-Saharan Africa."
"Insect vectors attract small fractions of the funding spent on studying and controlling the diseases they transmit," Hargrove says in his abstract. "Emphasis on vector studies for tsetse (Glossina spp) have, however, resulted in several novel vector and disease control options. Experiments carried out over the past 60 years at Rekomitjie Research Station in the Zambezi Valley of Zimbabwe, together with daily meteorological readings, provide a platform for studying the effects of climate change on the population dynamics of tsetse species occurring around Rekomitjie. Rates of pupal production and development, of abortion rates and of mortality among immature and adult stages of the flies are all highly correlated with temperature. Methods used to estimate such relationships in the field will be discussed and the relationships are used in explaining the sudden collapse in tsetse populations during the past decade, consequent on significant increases in temperature, particularly in the hot dry season."
Hargrove served as the inaugural director of the South African Centre for Epidemiological Modelling and Analysis (SACEMA). The precursors for MMED and DAIDD were launched in 2006 at the beginning of his directorship; he has been involved continuously as an instructor in the program since, according to his biography on ICI3D. Over the past nearly 50 years, Hargrove has combined fieldwork and mathematical epidemiology to understand the population dynamics and control of tsetse flies, the vectors of human African Trypanosomiasis.
He focuses his current research on the modelling population dynamics, with a particular focus on how increasing temperatures in Africa will affect tsetse distribution. This work involves improving estimation of mortality in adult and immature stages of the fly. Since 1999, he has also focused on the analysis and modelling of data in the world of HIV. Current interest are in improving the use of biomarkers for the accurate estimation of HIV incidence.
He holds a bachelor's degree in zoology (1968) from the University of Oxford; a master's degree in biomathematics (1981) from UCLA, and a doctorate in insect physiology (1973) from the University of London.
Department seminar coordinator is urban landscape entomologist Emily Meineke, assistant professor. For technical issues regarding Zoom connections, she may be reached at ekmeineke@ucdavis.edu. (See complete list of spring seminars.)
Resource:
SERVIR--From Space to Tsetse Fly
World Health Organization: Trypanosomiasis (Human African Sleeping Sickness)
- Author: Kathy Keatley Garvey
Meet Chryseobacterium kimseyorum, named for UC Davis distinguished professor Lynn Kimsey, director of the Bohart Museum, and her husband, forensic entomologist Robert "Bob" Kimsey, both of the Department of Entomology and Nematology.
“We've had a few things named after us but never bacteria--that's a first,” said Lynn Kimsey.
The story begins more than a decade ago when then UC Davis doctoral student Matan Shelomi, now an associate professor of entomology at National Taiwan University, Taiwan, was studying the digestive physiology of the stick and leaf insects, Phasmatodea, for his Ph.D, under the guidance of his major professor, Lynn Kimsey. He isolated and cultured bacteria from the guts and cages of the stick insects. Some of the species seemed new to science, but Shelomi had neither the time nor the resources to prove it then.
He stored the microbes inside the deep freezers of the Phaff Yeast Culture Collection, UC Davis Department of Food Science and Technology.
The years slipped by. So did the memory of isolating the bacteria. Then after becoming a professor himself, his graduate student, Chiao-Jung Han, discovered a new bacteria species inside a beetle. That prompted Shelomi to renew his interest in the microbes from the Bohart Museum.
"Thankfully, I kept all my notes from graduate school," says Shelomi, "so I was able to check and see which strains I had flagged as possibly new species. When I saw one of them was the same genus as the new microbe found in Taiwan, I realized this was an opportunity to describe them both together." So Shelomi emailed Kyria Boundy-Mills, curator of the Phaff Collection, “who had my old specimen revived and shipped across the Pacific.”
The abstract begins: “Two strains of Chryseobacterium identified from different experiments are proposed to represent new species. Strain WLa1L2M3T was isolated from the digestive tract of an Oryctes rhinoceros beetle larva. Strain 09-1422T was isolated from a cage housing the stick insect Eurycantha calcarata. Sequence analysis of the 16S rRNA and rpoB genes found both strains to be similar but not identical to other Chryseobacterium species. Whole-genome sequencing suggested the isolates represent new species, with average nucleotide identity values ranging from 74.6 to 80.5?%.”
Tabatha Yang, education and outreach coordinator of the Bohart Museum, relayed the news to a tour group visiting the insect museum on April 20. “I just used this story today with a tour group,” she told Shelomi. “I mentioned how your student was denied her dog's name. I love how this ties the Bohart and the Phaff Yeast collection together and then California and Taiwan.”
As for the stick insect, “It's pretty aggressive for a walking stick,” Lynn Kimsey said, noting that Andy Engilis, curator of the UC Davis Museum of Wildlife and Fish Biology, told her about his work in Papua New Guinea. “These walking sticks would actually chase rodents out of their burrows and take over the burrows to rest in,” she related. “That's pretty tough for a walking stick.”
Meanwhile, the Kimseys are enjoying their new namesake. Lynn Kimsey already has seven other species named for her:
- Mystacagenia kimseyae Cambra & Wasbauer 2020 (spider wasp)
- Oligoaster kimseyae Soliman 2013 (tiphiid wasp)
- Exaerate kimseyae Oliviera 2011 (orchid bee)
- Spilomena kimseyae Antropov 1993 (solitary wasp)
- Manaos kimseyae Smith (argid sawfly)
- Spintharina kimseyae Bohart 1987 (cuckoo wasp)
- Neodryinus kimseyae Olmi 1987 (dryinid wasp)
Bob Kimsey has as at least two species named for him: Acordulacera kimseyi Smith, 2010 (sawfly) and Grandiella kimseyi Summers & Schuster (mite).
Shelomi, a Harvard University graduate who received his doctorate from UC Davis in 2014, served as a National Science Foundation postdoctoral fellow at the Max Planck Institute for Chemical Ecology, Germany for two years before accepting a faculty position in 2017 at National Taiwan University.
Shelomi returned to UC Davis in 2017 to present a seminar on "Revelations from Phasmatodea Digestive Track Transcriptomics,” to the department.
- Author: Kathy Keatley Garvey
His seminar, "Telling The Whole Story: Using Native Caterpillars, Their Ecological Connections, and Novel Outreach Tools to Showcase the Importance of Biodiversity," begins at 4:10 p.m. The Zoom link:
https://ucdavis.zoom.us/j/95882849672
Jaffe relates that he will present "an original photograph and video-packed talk that explores backyard pollinators, plants, parasitoids, and the many caterpillars that are positioned at the center of it all. I will introduce a 'Whole Story' perspective of natural history study and appreciation that just might make you reconsider an herbivore's place in our world. Throughout the presentation, I will relate these topics to my experience with outreach education, showcase invaluable educational tools such as digital microscopes, and be available for discussion about The Caterpillar Lab's outreach techniques and how they might be incorporated into your own work."
Jaffe, a New England-based naturalist, photographer, and educator who works with native insects, is a native of eastern Massachusetts, where he spend his childhood "chasing birds, mucking through ponds, and turning over leaves." For the last seven years, he has been photographing caterpillars and organizing programs "to promote these special creatures to the public." He founded The Caterpillar Lab in 2008 and now "travels across the country working with museums, nature centers, schools, and individual teachers helping native insects find their place in our everyday lives."
Jaffe holds a bachelor's degree in ecology and evolutionary biology (2007) from Brown University, Providence, Rhode Island, and a master's degree in environmental science (2014) from Antioch University New England, Keene, N.H. He served as a lab technician at Harvard Organismic and Evolutionary Biology Labs for a year, gaining experience with caterpillar and ant care and reproduction, ant-caterpillar interaction research and experimental design/implementation; morphological study; native insect collection; natural history guided walks.
On his LinkedIn page, Jaffe describes The Caterpillar Lab, a non-profit corporation, as fostering "greater appreciation and care for the complexity and beauty of our local natural history through live caterpillar educational programs, research initiatives, and photography and film projects. We believe that an increased awareness of one's local environment is the foundation on which healthy and responsible attitudes towards the broader natural systems of this world is built."
The Caterpillar Lab "works with native New England caterpillar species as a resource for art, education, science, and other natural history pursuits," he writes, adding that he shows his fine art collection of caterpillar photographs at galleries and museums across the country; offers educational workshops; and works with BBC as a consultant, providing caterpillars and expertise.
Department seminar coordinator is urban landscape entomologist Emily Meineke, assistant professor. For technical issues, she may be reached at ekmeineke@ucdavis.edu. (See complete list of spring seminars.)
- Author: Kathy Keatley Garvey
Shey won the $5000 Francesca Miller Undergraduate Research Award that will fund six weeks of full-time summer research. And, judges scored her poster, “A Nanobody-Based Immunoassay for Detecting Moldy Marijuana,” as the top research poster in the undergraduate student competition.
The symposium, held recently in the UC Davis Conference Center, featured cutting-edge research in chemical biology, organic, and pharmaceutical chemistry. It memorializes Professor Miller (1940-1998) the 1985-90 chair of the Department of Chemistry and the 1997-1998 chair of the Academic Senate.
“We're very proud of Rachel,” said Hammock, who holds a joint appointment with the Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center. “Rachel winning the undergraduate research award as well as the first-place award for her poster on her research—that's no surprise. She is enthusiastic about science and has wonderful collaborations with our scientists. She is one of those rare people who can cross disciplines, and in this case, integrate molecular biology, chemistry, and analytical chemistry to address a serious problem in the world food supply. Not only that, but she makes the lab had more fun place to be.”
In her abstract, co-authored with mentor Hammock and project scientist Mark McCoy of the Hammock lab, Shey wrote:
“Have you ever forgotten about a bagel on the counter and come back a few days later to find that it has grown a thin layer of fuzzy green mold? Most people know not to eat it, but why not? Aspergillus fungus produces a toxin called aflatoxin, which is the reason moldy bread, bitter peanuts and other foods may not be safe to eat. Aspergillus grows on virtually all major crops in the world, and aflatoxin is present wherever Aspergillus grows.”
Shey related that “the first step is to optimize the concentrations of the substrate, coating antigen, and nanobody for the assay; once this is done, we can assay extracts of hemp bud samples. These samples tend to contain other reactive molecules that can create unusual signals by binding to nanobodies undesirably. This is known as the “matrix effect” and must also be controlled for, either by further diluting the sample, while paying close attention to the limit of detection, or processing the samples in a different way to reduce the amount of potential interference.”
“Cannabis is highly regulated in California,” Shey pointed out, “but batches of cannabis that fail testing are usually sold on the black market rather than at a regulated dispensary. Consumers who decide to run the risk of purchasing cannabis from an unregulated seller would also benefit from immunoassays for monitoring the levels of various pesticides and known contaminants, including aflatoxin. This immunoassay could be useful for not only commercial labs analyzing cannabis, but also consumers purchasing cannabis illegally.”
Shey also presented her poster research at two other UC Davis conferences this year: the Undergraduate Research, Scholarship and Creative Activities Conference (URSCA) and the 2023 Richard LaRock Conference.
Rachel, from Walnut Creek, and home-schooled from K-12 in the RAN Academy (RAN is an acronym for Rachel and her brothers Aaron and Nicholas), received her high school diploma in 2020. She enrolled at UC Davis in September 2020 and joined the Hammock lab in March 2022.
“I was really drawn to entomology because I've loved playing with insects ever since I was a kid,” Rachel said. “When I took organic chemistry, I fell in love with the unique style of problem solving and I grew passionate about its practical aspects as well.”
In the Hammock lab, she helps in immunoassay experiments, delivers presentations to the lab, and learns about research and science. “I am developing proficiency with ELISA (enzyme linked immunosorbent assay) and phage work,” Shey said. She is working on an independent project funded by an Innovation Institute for Food and Health Undergraduate Research Fellowship (IIFL) from the UC Davis Undergraduate Research Center. It involves the detection of aflatoxin in mouse brain tissue.
Shey also is a research assistant (since November 2022) in the lab of Cody Ross Pitt, assistant professor, UC Davis Department of Chemistry, where she is learning organic synthesis methods, including setting up air-sensitive reactions, working up reactions, using columns to purify the crude material, and operating a rotary evaporator (rotovap).
She has served a general and organic chemistry tutor or the UC Davis Academic Assistance and Tutoring Center (AATC) since September 2021. She staffs the drop-in area in the library and the online Zoom drop-in room for several hours each week. “I assist students with chemistry questions with the goal of helping my students develop study skills.”
Shey also worked part-time for almost two years as a city news reporter for the California Aggie, the UC Davis student-run newspaper.
Her career plans: to study organic chemistry and obtain a doctorate in chemistry. “I would love to work in medicinal chemistry or agrochemistry.”
“When I first talked to her she was excited over epoxides as such interesting chemical functionalities,” said Hammock, known for his expertise in chemistry, toxicology, biochemistry and entomology. Early in his career, he founded the field of environmental immunoassay, using antibodies and biosensors to monitor food and environmental safety, and human exposure to pesticides. His groundbreaking research in insect physiology, toxicology led to his development of the first recombinant virus for insect control.
“I saw Barry Sharpless last week, who like Linus Pauling, won two Nobel Prizes," Hammock said. She reminds me of Barry. The world needs more undergrads like Rachel.”
